A Postquantum Linkable Ring Signature Scheme from Coding Theory

Abstract

Linkable ring signatures (LRSs) are ring signatures with the extended property that a verifier can detect whether two messages were signed by the same ring member. LRSs play an important role in many application scenarios such as cryptocurrency and confidential transactions. The first code-based LRS scheme was put forward in 2018. However, this scheme was pointed out to be insecure. In this paper, we put forward a code-based LRS scheme by constructing a new Stern-like interactive protocol and prove that it meets the security requirements of LRSs. We also give the specific parameters and the performance on the platform of our scheme.